Chapter 30: Connecting Your LAN to the Internet

Chapter Introduction

If you have a LAN, connecting the whole LAN to the Internet makes more sense than connecting each individual computer on the LAN. By connecting the LAN to the Internet, all of the PCs on the LAN can share one Internet account and one phone line or cable connection. Large companies have connected their internal networks to the Internet for years, and small offices and home LANs can do the same.

For the PCs on a LAN to use the Internet, you must configure each PC to communicate using TCP/IP, the Internet's communication protocol. Then a program or device must route the TCP/IP information between the LAN and the Internet; you can use a dedicated device (a router) or a gateway program running on a PC.

Windows XP (like Windows Me and 2000) comes with Internet Connection Sharing (ICS), a gateway program that can route information between a LAN and the Internet. This chapter describes how to configure the ICS server program on the computer connected to the Internet and the ICS client settings on the other computers on the LAN. Once ICS (or another gateway) is installed, everyone on the LAN can send and receive e-mail, browse the Web, and use other Internet programs at the same time. Windows comes with troubleshooting tools for making sure that your ICS system works.

Neither Internet Connection Sharing nor Internet Connection Firewall is supported under Windows XP 64-Bit Edition.

Virtual Private Networking (VPN) is a system that lets your organization create a private LAN over the Internet. Windows comes with a VPN program that enables your computer to connect to a virtual private network.